1. Field of Invention
The present invention relates to a horn switch device for a steering wheel. More particularly, the present invention relates to a horn switch device mounted in a steering wheel of a vehicle so as to generate an alarm sound by a user's intention.
2. Background Art
In general, an airbag assembly and a horn switch device are mounted in a steering wheel of a vehicle. Here, the airbag assembly safely protects a driver from a collision or overturn of the vehicle, and the horn switch device generates an alarm sound by a driver's intention.
The horn switch device is disposed at a rear side of the airbag assembly disposed at a front side of the steering wheel. When the driver presses the airbag assembly, the horn switch device forms a contact point, thereby generating a horn sound.
As the horn switch device mounted together with the airbag assembly in the steering wheel, various types of ones have been disclosed in Korean Patent No. 10-0477245, Korean Patent Application Publication Nos. 10-2006-0067563 and 10-2006-0020748, Japanese Patent Application Publication No. 2006-331657, etc.
An example of the horn switch device will be described as follows. FIGS. 1 and 2 are perspective and front views showing a conventional horn switch device for a steering wheel. FIG. 3 is a sectional view showing an operating state of the conventional horn switch device. As shown in FIGS. 1 and 2, a steering wheel 100 and an airbag assembly 110 are provided, and the airbag assembly 110 is disposed inside the steering wheel 100. The airbag assembly 110 is mounted in the steering wheel 100 in a bolt fastening structure.
The airbag assembly 110 includes an airbag module 120 and a mounting plate 130. The airbag module 120 is elastically supported by a horn spring 140 disposed at a rear side thereof, and the mounting plate 130 is fastened to the steering wheel 100 through a mounting point 150 at a lower end thereof.
Thus, if a driver presses an arbitrary point on the front side of the airbag module 120, the airbag module 120 presses the horn spring 140 so that a contact point mounted in the mounting plate 130 contacts a contact point mount in the airbag module 120, thereby ringing a horn.
However, the conventional horn switch device has several problems as follows. As shown in FIG. 3, if the airbag module 120 is pressed to operate the horn, that is, if a cover of the airbag module 120 is pressed, the horn spring 140 acts as a hinge point 160 as the airbag module 120 is restricted by the horn spring 160. Accordingly, one side of the airbag module 120 is inclined with the trace of an arc having long radius and small angle, thereby contacting a contact point of the horn.
Therefore, the gap between the airbag module 120 and the steering wheel 100 is narrowed as can be seen in FIG. 3. If the gap is narrowed as described above, there are a lot of limitations in designing the horn switch device. Further, the horn does not ring due to a lack of the gap, and therefore, it is highly likely that the horn switch device may be decided as a failure.
In addition, if the gap is considerably increased for the purpose of gap insurance, the inside of the steering wheel may be seen in appearance.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.